This application further expressly incorporates by reference the disclosure of the following: U.S. Pat. No. 4,949,414 issued Aug. 21, 1990 to Thomas et al. titled “Modular Low Air Loss Patient Support System and Methods for Automatic Patient Turning and Pressure Point Relief,” U.S. Pat. No. 5,794,288 issued on Aug. 18, 1998 to Soltani et al. titled “Pressure Control Assembly for an Air Mattress,” U.S. Pat. No. 6,212,718 issued on Apr. 10, 2001 to Stolpmann et al. and titled “Air-Over-Foam Mattress,” U.S. Pat. No. 6,240,584 issued on Jun. 5, 2001 to Perez et al titled “Mattress Assembly,” and U.S. Pat. No. 6,415,814 issued on Jul. 9, 2002 to Barry D. Hand et al. titled “Vibratory Patient Support System,” and U.S. patent application Ser. No. 09/701,499, now U.S. Pat. No. 6,582,456 issued on Jun. 24, 2003 to Hand et al. and titled “Heated Patient Support Apparatus.” This application additionally expressly incorporates by reference the PrimeAire® Therapy Surface and the SilkAir® Therapy System both marketed by Hill-Rom located in Batesville, Ind. and at 4349 Corporate Road, Charleston, S.C. 29405.
The present invention relates generally to patient supports and more specifically patient supports including a spacing structure and an inflatable layer, such as a plurality of air bladders. As used herein, the term spacing structure for convenience is defined to include at least suitable types of “indented fiber layers” and suitable types of “three dimensional engineered materials.”
The present invention relates to mattress or cushion structures designed to improve pressure distribution while reducing the overall thickness of the mattress or cushion. The mattress or cushion structures of the present invention illustratively include a foam base on which a spacing structure such as one or more indented fiber layers or other three dimensional engineered material are placed. The base and the spacing structure are illustratively encased in a cover to provide a mattress or cushion.
While the use of foam in mattresses and cushions is known and the use of three dimensional engineered material is known, the present invention relates to a unique combination of a foam base and three dimensional engineered material layers placed on the foam base. The present invention also contemplates that, in addition to the foam base, an air cushion layer may be used with the foam and the indented fiber layers to further enhance the pressure distribution capabilities of the mattress or cushion. In some embodiments, the base may be primarily, if not solely, an air cushion which is enhanced by at least one three dimensional engineered material layer. In other embodiments, water filled bladders, springs, or zones filled with beads, gel or other such material may be used in the base.
Reference is made to U.S. Pat. Nos. 5,731,062 and 5,454,142 disclosing the three dimensional fiber networks made from textile fabrics that have projections and optional depressions which are compressible and return to their original shape after being depressed. U.S. Pat. Nos. 5,731,062 and 5,454,142 are owned by Hoechst Celanese Corporation, Somerville, N.J. Such material is a synthetic thermoplastic fiber network in flexible sheets having projections and/or indentations for use as cushions and/or impact-absorbing components. The descriptions of such patents are incorporated herein by reference to establish the nature of one example of three dimensional engineered material or indented fiber layer disclosed herein. It will be appreciated, however, that the present invention contemplates use of such layers whether or not they are supplied by Hoechst Celanese Corporation and whether or not they are similar to the SPACENET® product.
It is understood that other types of materials similar to the SPACENET® material may be used. For example, the material may be any type of three dimensional engineered material having a spring rate in both the X and Y axes. Preferably such material is open and breathable to provide air passage through the layer. For instance, Model No. 5875, 5886, 5898, and 5882 materials from Muller Textile, a molded thermoplastic spacer matrix material available from Akzo Nobel, or other suitable material may be used. Therefore, the term “three dimensional engineered material” is meant to include any of these types of materials used in accordance with the present invention.
The concept is to use three dimensional fiber layer networks made from textile fibers that have projections and optional depressions or other structures which are compressible and which return to their original shapes after being compressed or the equivalents of such layers. The SPACENET® fiber networks are typically made by thermo-mechanical deformation of textile fabrics that are in turn made from thermoplastic fibers. In accordance with the present invention other types of layers with individual spring or spring-like protrusions may be used.
It has been found that two or more such layers, hereinafter referred to as “indented fiber layers” for convenience will assist in the pressure distribution when incorporated into an assembly comprising a well designed support base which may comprise foam or some combination of foam and air. The SPACENET® layers are examples of such “indented fiber layers.” As used herein, the term spacing structure for convenience is defined to include at least suitable types of “indented fiber layers” and suitable types of “three dimensional engineered materials.”
In the fabrication of a seat cushion, it has been found that improved pressure distribution is provided when the seat cushion is designed to form fit the buttocks of the person sitting on the cushion. When such seat cushions are used by patients who have experienced skin tissue breakdown on their buttocks, the improved pressure distribution will permit the patients to sit up in chairs for greater periods of time for the therapeutic value that accomplishes.
An apparatus of the present invention is therefore configured to support at least a portion of a body thereon. The apparatus includes a cover having an interior region, a base located within the interior region, and a three dimensional engineered material located within the interior region above the base. The three dimensional engineered material and the base cooperate to provide support for the body.
In one embodiment, an apparatus configured to support at least a portion of a body thereon is provided comprising a base portion including a plurality of zones, each zone having associated support characteristics, the base portion configured to provide a static support for the body; a pressure distribution layer supported by at least a first zone of the base portion, the pressure distribution layer including a spacing structure configured to provide air passage therethrough and to distribute pressure from the body over a greater area of the first zone; and a cover positioned between the pressure distribution layer and the portion of the body to be supported, the cover being coupled to a first source of air to provide air circulation through the pressure distribution layer. In one example, the base portion includes a plurality of inflatable bladders, each of the plurality of zones including at least one of the plurality of bladders. In one variation, the apparatus further comprises a controller configured to control the pressure in each support zone of the plurality of support zones of the base portion, the controller configured to generally pressurize the first support zone at a first pressure and to generally pressurize a second support zone at a second pressure, the second pressure differing from the first pressure when the base portion is configured to provide a static support.
In a further embodiment, an apparatus configured to support at least a portion of a body thereon is provided comprising an inflatable first layer including a plurality of support zones, a second layer positioned between the first layer and the portion of the body to be supported, the second layer including a spacing structure, and a controller configured to control the pressure in each support zone of the plurality of support zones of the inflatable first layer. In one example, the inflatable first layer is configured to provide a static support surface wherein a first support zone is configured to be generally pressurized at a first pressure and a second support zone is configured to be generally pressurized at a second pressure, the second pressure differing from the first pressure. In another example, the inflatable first layer is configured to provide at least one therapy to the portion of the body supported thereon. In yet another example, the apparatus further comprises a cover configured to confine at least the second layer of the first layer and the second layer and including a first portion positioned adjacent the portion of the body to be supported, the first portion including a moisture vapor permeable material. In one variation, the cover is coupled to a source of air to provide air circulation through the second layer and the through the moisture vapor permeable material of the first portion of the cover.
In another embodiment, an apparatus configured to support at least a portion of a body thereon is provided comprising an inflatable first layer including a plurality of support zones, the plurality of support zones including a first support zone which generally corresponds to the chest region of the body, a second layer positioned between the first layer and the portion of the body to be supported, the second layer comprising a spacing structure, a controller configured to control the pressure of each support zone of the first inflatable layer and further to control the pressure of the first support zone to provide a percussion therapy to the chest region of the body, and a cover positioned between the second layer and the portion of the body to be supported. In one example, the cover defines an interior region, the second layer being positioned within the interior region. In one variation, the apparatus further comprises a source of air coupled to the cover such that air is forced through the second layer. In another example, the cover defines an interior region, the second layer being positioned within the interior region, and at least a portion of a top surface of the cover is made from a breathable material, the portion of the top surface and the second layer cooperating to provide cooling for the body supported on the portion of the lop surface. In one variation, the apparatus further comprises a source of air coupled to the cover to provide air circulation through the second layer.
Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of the illustrated embodiments exemplifying the best mode of carrying out the invention as presently perceived.